JPS63215860A - Waste heat utilizing device for engine - Google Patents

Abstract

PURPOSE:To utilize the waste heat effectively by recovering the exhaust gas loss heat amount and the coolant loss heat amount which occupy a large ratio of all the heat amount of an engine other than the net effective work, by an oil coolant whose boiling point is higher than that of water, and evaporating the water by the heat of the coolant. CONSTITUTION:At a cylinder block 11 and a cylinder head 12 of an engine 10, coolant passages 13 and 14 the oil is circulated through are formed, to which the oil from an oil pump 15 is fed. The first heat exchanger 25 is arranged to cover an exhaust manifold 27 of the engine 10, and its inlet 28 is connected to the outlet 18 side of the coolant passage 14 through a duct 19. To the outlet 29 of the first heat exchanger 25, the inlet 33 of a vapor generator 30 is connected, and the water in a water duct 32 linking to the inside of the vapor generator 30 is heated to evaporate. And the outlet of the first heat exchanger 25 is connected to the chamber 43 of the second heat exchanger 40, and the oil coolant is arranged to be cooled by the sea water delivered by a pump 52.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a waste heat utilization device provided in an engine cooling system. More specifically, the present invention relates to a device for generating steam using engine waste heat.

[Conventional technology and its problems] When the total heat of the engine is accounted for, the net effective work is:
It is usually divided into four types: ■The amount of heat lost to exhaust gas and radiant heat; ■The amount of heat lost to the refrigerant; and ■The work required to drive friction and auxiliary equipment. Among the amount of heat other than the net effective work ((2)), the amount of heat lost to the exhaust gas ((2)) and the amount of heat lost to the refrigerant ((2)) account for a large proportion.

Even if you try to recover and use the heat of these ■ and ■ in the engine refrigerant, in a water-cooled engine, the refrigerant water boils at around 100 degrees Celsius at atmospheric pressure, so it is necessary to use that thermal energy effectively. There was a limit.

An object of the present invention is to provide an engine waste heat utilization device that recovers and effectively utilizes both the amount of heat lost to the exhaust gas (I) and the amount of heat lost to the refrigerant (I).

[Means for Solving the Problems] The present inventor has discovered that water can be vaporized by using oil with a boiling point of 200°C or higher as the refrigerant for the engine, and by making this refrigerant possess both the above-mentioned heat quantities (1) and (2). The present invention was achieved by paying attention to the fact that the temperature of the refrigerant can be raised to a certain temperature.

To explain with reference to the accompanying drawings, the engine waste heat utilization apparatus of the present invention is such that the refrigerant of the engine 10 is made of oil, the inlet 28 of the refrigerant passage 26 is connected to the outlet 18 of the refrigerant passage 14 of the engine 10, and a first heat exchanger 25 that heats the oil discharged from the engine 10 to at least a temperature necessary to vaporize water using the exhaust heat of the engine 10; A steam generator 30 connected to the outlet 29 of the refrigerant passageway 31 and having a water conduit 32 disposed in the refrigerant passage 31 so that the water in the water conduit 32 can be vaporized and taken out using heated oil discharged from the outlet 29; The inlet 47 of the refrigerant passage 41 is connected to the outlet 35 of the refrigerant passage 31 of the steam generator 30, and the outlet 48 of the refrigerant passage 41 is connected to the inlet 17 of the refrigerant passage 13 of the engine 1o. a second heat exchanger 4° that water-cools the oil to be discharged; and an oil pump 15 that circulates the oil to each refrigerant passage of the engine 10, the first heat exchanger 25, the steam generator 30, and the second heat exchanger 40. It is prepared.

[Function] By using oil with a boiling point of 200°C or higher as the refrigerant, the oil that has taken heat from the engine IO is transferred to the first heat exchanger 2.
In step 5, the water is further heated to a temperature necessary to vaporize the water using the exhaust heat of the engine 1o. This heated oil is guided to a steam generator 30 and steam is taken out from a water conduit 32. The oil that has passed through the steam generator 3o is water-cooled in a second heat exchanger 40 and returns to the engine 10 as a refrigerant.

[Example] Next, an example of the present invention will be described in detail based on the drawings.

In the figure, IO is a marine engine that uses oil as a refrigerant.

The engine 10 has a cylinder block 11 and a cylinder radius 12. Refrigerant passages 13 and 1 through which oil flows through the cylinder block 11 and cylinder head 12, respectively.
4 is provided. The refrigerant passages 13 and 14 are supplied with oil from an oil pump 15 via a conduit 16 and an inlet 17 of the refrigerant passage 14. Refrigerant passage 13
The oil supplied to the cylinder block 11 and 14 is
The refrigerant flows through the rads 12 into the cylinders and reaches the outlet 18 of the refrigerant passage 14. One end of a conduit 18 is connected to this outlet 18, and a thermostat 20 is provided in the middle of this conduit 18. The thermostat 20 and the oil pump 15 are connected by a conduit 21.

25 is a first heat exchanger. This heat exchanger 25 is provided with a refrigerant passage 26 through which oil flows. Refrigerant passage 26
An exhaust manifold 27 of the engine 10 is disposed therein. The second inlet of the refrigerant passage 26 is connected to the other end of the conduit 18 .

30 is a steam generator. This steam generator 30 is provided with a refrigerant passage 31 through which oil flows. Refrigerant passage 31
A water guide pipe 32 folded multiple times is disposed inside. An inlet 32 a and an outlet 32 b of the water pipe 32 are provided outside the refrigerant passage 31 . The inlet 33 of the refrigerant passage 31 is connected via a conduit 34 to the outlet 29 of the refrigerant passage 2B.

40 is a second heat exchanger. This heat exchanger 40 is provided with a tubular refrigerant passage 41 through which oil flows. A plurality of seawater passages 42 are arranged within this refrigerant passage 41 .

Chambers 43 are provided at both ends of the refrigerant passage 41 and the seawater passage 42.
The chamber 43 is divided by a partition wall 45 into an inner chamber 43a and an outer chamber 43b, and the chamber 44 is divided by a partition wall 46 into an inner chamber 44a and an outer chamber 44b. A large number of refrigerant inlets 47 are opened in the peripheral wall of the refrigerant passage 41 in the inner chamber 43a of the chamber 43, and the inner chamber 4 of the chamber 44
A large number of refrigerant outlets are provided on the peripheral wall of the refrigerant passage 41 4a. In addition, both ends of the seawater passage 42 are open to form an outer chamber 43.
b and 44b.

The inlet 47 of the refrigerant passage 41 is connected to the outlet 35 of the refrigerant passage 31 via the inner chamber 43a and the conduit 48! ! Continued. The outlet 48 is also connected to the oil pump 15 via the inner chamber 44a and a conduit 50. Further, the entrance of the seawater passage 42 is connected to the seawater conduit 51 via the outer chamber 44b. A seawater pump 52 is provided in the middle of this seawater conduit 51. Further, the outlet of the seawater passage 42 is connected to the seawater conduit 5 via the outer chamber 43b.
Connected to 3.

The operation of the engine waste heat utilization device having such a configuration will be explained.

First, the refrigerant, that is, oil, supplied by the oil pump 15 to the refrigerant passage 13 of the cylinder block 11 and the refrigerant passage 14 of the cylinder head 12 is heated by the combustion temperature of the engine 10. If this oil temperature is below the specified temperature,
Thermostat 2G does not open and oil circulates through conduit 21.

When the oil temperature exceeds a predetermined temperature, the thermostat 20 opens and the oil flows into the refrigerant passage 26 of the first heat exchanger 25 through the conduit 19. Here the oil is in the exhaust manifold 2
It is heated by the exhaust heat from Step 7, and reaches a temperature of 140°C or higher, which is the temperature required to generate low-pressure steam, for example.

The oil heated by the first heat exchanger 25 is transferred to the steam generator 3
0 into the refrigerant passage 31. Here, the oil is in water conduit 3
2 to vaporize the water flowing through the water pipe 32. This steam is taken out from the outlet 32b of the water pipe 32 and used for external work of the engine 10.

The oil heat-exchanged in the steam generator 30 is transferred to the second heat exchanger 4
The refrigerant flows into the refrigerant passage 41 of No. 0, where it is further cooled by seawater to a temperature of 100° C. or less. The cooled oil flows into the engine 10 again through the oil pump 15.

In the above example, a non-supercharged marine engine was used as the engine lO, but the present invention is not limited to this. In other words, even in the same marine engine, oil can be passed around the casing of the turbocharger. By doing so, the oil temperature can be raised more effectively. In addition to ships, it can also be applied to stationary and vehicle engines.

[Effects of the Invention] As described above, according to the present invention, the amount of heat lost in the exhaust gas and the amount of heat lost in the refrigerant, which account for a large proportion of the total heat of the engine other than net effective work, can be reduced by using the oil refrigerant, which has a higher boiling point than water. By using the heat of the recovered oil refrigerant to vaporize water, engine waste heat can be effectively used.

[Brief explanation of the drawing]

The figure is a configuration diagram of a waste heat utilization device for an engine according to an embodiment of the present invention. 10: Engine, 13, 14: Engine refrigerant passage. 15 oil pump, 17: engine refrigerant passage inlet,
18: Engine refrigerant passage outlet, 25: First heat exchanger,
26: refrigerant passage of the first heat exchanger, 27: exhaust manifold, 28: refrigerant passage inlet of the first heat exchanger, 29; refrigerant passage outlet of the first heat exchange base, 30: steam generator, 31: steam generation 32: Water conduit pipe, 33: Steam generator refrigerant passage inlet, 35: Steam generator refrigerant passage outlet, 40:
Second heat exchanger, 41: Refrigerant passage of second heat exchanger, 42:
Seawater passage, 47: Second heat exchanger, refrigerant passage inlet of vessel, 48
: Refrigerant passage outlet of the second heat exchanger.

Claims (1)

[Scope of Claims] The refrigerant of the engine is made of oil, the inlet of the refrigerant passage is connected to the outlet of the refrigerant passage of the engine, and the oil discharged from the refrigerant passage of the engine is converted into at least water by the exhaust heat of the engine. a first heat exchanger that raises the temperature to a temperature necessary to vaporize the refrigerant, an inlet of a refrigerant passage is connected to an outlet of the refrigerant passage of the first heat exchanger, and a water conduit pipe is disposed within the refrigerant passage. , a steam generator configured to vaporize water in the water conduit and take it out using the oil discharged from the refrigerant passage of the first heat exchanger; and an inlet of the refrigerant passage of the steam generator. a second heat exchanger connected to an outlet of the engine, and an outlet of a refrigerant passage connected to an inlet of a refrigerant passage of the engine, for water-cooling oil discharged from the refrigerant passage of the steam generator; and an oil pump that circulates through each refrigerant passage of the first heat exchanger, the steam generator, and the second heat exchanger.